A weather balloon is sent up from the South Pole to measure the ozone layer

NASA photo showing the hole in the ozone layer over Antarctica

The ozone layer is a layer of ozone high up in the Earth's atmosphere stratosphere, between approximately 10 kilometres and 50 kilometres above Earth’s surface. The exact amount of ozone varies, depending on the seasons and the location. This layer absorbs between 93 and 99 per cent of the ultraviolet radiation from the sun. This radiation is dangerous to living organisms on Earth.